1. Field of the Invention
The present invention relates to an advantageous and novel process of producing pancreatin of a high amylolytic, lipolytic, and proteolytic activity, and more particularly to such a continuous process of producing pancreatin while at the same time considerably reducing the bacterial count and completely eliminating the undesirable germs therein, and to a pancreatin preparation which is substantially free of germs as they are to be excluded in accordance with the provisions of the U.S. Pharmacopeia XVIIIth Revision.
2. Description of the Prior Art
Deep-frozen pancreas glands are usually employed as starting materials for producing pancreatin because only frozen material can be stored without considerable losses of enzyme activity for a prolonged period of time. The preferred starting materials are the pancreas glands of hogs due to their high content of amylolytic and lipolytic activities.
A number of different processes for producing pancreatin are described in the literature. Thus, an extract in which the pro-enzymes of the proteases are activated by the addition of trypsin or enterokinase is produced, for instance, by treating and extracting the comminuted, frozen, or thawed glands with water, salt solutions, or solvents, such as dilute glycerin, 25% ethanol, 20% acetic acid. Such an extract is subjected subsequently to precipitation with inorganic salts, organic solvents, or tannin and is then converted by careful drying into a powder.
Pancreatin can also be produced by removing the water at a low temperature from the comminuted gland material, for instance, by freeze-drying, vacuum drying or azeotropic distillation, with subsequent removal of fat by extraction with organic solvents or by simultaneous dehydration and defattening, for instance, by means of acetone, alcohols, or, alternatively, by mixtures of acetone and an ether, followed by drying.
According to British Pat. No. 822,741 of Oct. 28, 1959 and French Pat. No. 1,295,302 of July 8, 1962, pancreas glands are first subjected to a mechanical fat removal treatment, are comminuted to a particle size of 1 mm. to 2 mm., are further subjected in a container to fat extraction by means of diethyl ether in batch procedure, and are subsequently converted by centrifuging into three phases, namely, an ether-fat phase, the pancreas juice-phase, and the meat residue. Pancreatin products of therapeutic value are precipitated from the pancreas juice by the addition of ammonium sulfate.
At the present time hog pancreas glands to be used as starting material for the production of pancreatin are collected exclusively on a large scale from slaughterhouses and meat packaging plants. When removing the pancreas glands from the gastric-intestinal bundles of freshly slaughtered animals, contamination cannot be prevented under normal slaughterhouse conditions. Therefore, germ counts, i.e. the number of pathogenic plus apathogenic germs present in each gram of material, have been found to amount to 10.sup.4 /g. to 10.sup.8 /g. found on examination of glands collected under such conditions.
Microbially-pure drugs are generally subdivided into three groups, namely into sterile preparations, into preparations free of pathogenic germs, and into preparations which are of a low germ content. Such preparations have been produced by the pharmaceutical industry for some time in the form of injectable, dermatological and ophthalmological preparations, and in the form of preparations applicable to the mucous membranes. Recently, however, more and more attempts have been made to also produce orally administrable preparations of a substantial microbial purity. But meeting this requirement is quite difficult when producing biological preparations derived from animal organs.
Pancreatin, as a natural biological product with its highly sensitive enzyme components, is contaminated with respect to type and count of germs to a varying extent and frequently is not free of pathogenic germs.
Attempts have already been made to reduce the bacterial count or germ number in pancreatin preparations. Thus, for instance, B. Schlatter treats pancreatin with isopropanol and water or with .gamma.-rays or with both simultaneously as described in his dissertation deposited at the Technical University of the Swiss Federation at Zuerich 1971; and in Pharm. Acta Helvetiae Vol. 49, page 41 (1974). The mixture of solvents is removed by azeotropic distillation after the isopropanol-water treatment.
A treatment of pancreatin with .gamma.-rays in order to reduce the germ count has also been described in Czechoslovakian Pat. No. 147,274.
Experiments to reduce the bacterial count or germ number by a treatment with ethylene oxide have furthermore been carried out by A. Libicky et al. as described in "Die Pharmazie" vol. 22 (1967), page 311, and vol. 23 (1968), page 21.
Reduction of the germ content in pancreatin is effected in the manner described in German Offenlegungsschrift No. 2,135,025. Said process consists in treating pancreatin with halogenated hydrocarbons of a boiling point between 15.degree. and 100.degree. C. or, respectively, with aliphatic ketones in the presence of water and cellulose derivatives. Halogenated hydrocarbons which are suitable for this treatment are exclusively chlorinated hydrocarbons, namely methylene chloride and chloroform. 100 g. of the resulting pourable pancreatin granulate are free of Salmonella germs and 1 g. thereof is free of Enterobacteria and Pseudomonas bacteria and the total bacterial count or germ number therein is lower than 10.sup.4.
According to the process described in German Offenlegungsschrift No. 2,106,706 pancreatin is mixed with calcium compounds and the mixture is heated at 82.degree. C. under atmospheric pressure for several hours in order to destroy Salmonella bacteria.
While pancreatin is used as a starting material in the above-mentioned processes for reducing the germ number, there has become known also a process for destroying Salmonella bacteria when using pancreas glands as starting material. See E. J. G. Glencross in Brit. Med. Journal vol. 2, page 376 (1972). According to said process, the pancreas glands are treated with an aqueous solution of hypochlorite, are comminuted, ground, dried in a vacuum, and subjected to a defattening process.
All the above-described processes for reducing the germ number or bacterial count of pancreatin preparations are very complicated and, in addition thereto, are accompanied by considerable losses in activity.